The present invention relates to yarns used for outdoor fabrics. More particularly, the invention relates to a blended or composite self-coating yarn which, when combined with other effect yarns, is capable of stabilizing and strengthening such fabrics without the use of a latex back coating or other topical treatments.
Blended or composite yarns formed of high melt and low melt fibers or filaments are generally known for various applications. Examples of such yarns are described in U.S. Pat. Nos. 5,651,168; 5,397,622; and 5,536,551. None of the above yarns, however, are appropriate for or intended for use as a stabilizing yarn for outdoor applications requiring a high degree of dimensional stability, and strength. The term xe2x80x9coutdoor fabricsxe2x80x9d as used herein is defined as fabric for awnings, tents, sling fabric for furniture, cushions, umbrellas, marine applications, convertible tops, and the like. The term xe2x80x9ceffect yarnxe2x80x9d is intended to mean yarns, such as acrylics, polyester, and polypropylene, which are used in the construction of aesthetically appealing, softer blend decorative fabrics.
Many yarns are inappropriate for outdoor use unless they are solution dyed and UV stable. Such yarns that are appropriate include acrylics, high melt polyester, nylon, and high melt polypropylene. The aforementioned yarns are not considered to be particularly dimensionally stable nor resistant to abrasion in open weave structures. As a result, in such applications the fabric is either provided with a latex backing to improve stability or it is used with the recognized deficiencies.
Thus, there is a need for a stabilizing yarn suitable for use with effect yarns in the fabrication of open weave fabrics to be utilized in outdoor applications wherein such fabrics will be imparted with improved abrasion resistance, weave stability, strength and the other characteristics described hereinabove.
Use of a latex backing is a recognized impediment to the use and acceptance of fabrics in outdoor applications. The application of a latex backing is expensive, requiring specialized machinery, additional chemical cost and, at times, slower tenter speeds or multiple passes through the tentering operation. It also provides a greater opportunity for mildew problems and renders a stiffer fabric with only one side available for decorative patterning.
The present invention, therefore, is directed to a novel composite or blended stabilizing yarn intended for use with effect yarns to fabricate an open weave fabric structure, or, when used in more tightly woven fabrics results in a fabric appearing and feeling to be heavier than it actually is. Outdoor fabrics, which include as a component the yarns of the present invention, achieve strength and dimensional stability without being heavy and/or tightly woven. By use of the novel stabilizing yarn of the present inventbn, a better hand is imparted and the resulting fabrics are made to xe2x80x9cfeelxe2x80x9d heavier than they actually are. The stabilizing yarn includes a binder constituent which may be a filamentary constituent of a composite yarn or a staple fiber constituent of a blended yarn. The yarn is used with effect yams in a woven fabric. The binder constituent is then released during the tentering operation and provides the resulting fabric with superior weave stability, abrasion resistance and esthetic characteristics or properties without the need for latex back coatings. Wicking capability is another important characteristic for quick drying after exposure to water or other liquids.
The yarn of the present invention, therefore, is a self-coating composite stabilizing yarn having one or more low melt constituent and one or more high melt constituent. The low and high melt constituents are intermingled in one of several yarn forming operations to provide a composite or blended yarn having a denier in the range of 400 to 4,000 or equivalent yarn count. By xe2x80x9clow meltxe2x80x9d the present invention envisions a constituent having a melt temperature in the range of 240xc2x0 F. and 300xc2x0 F. On the other hand, the xe2x80x9chigh meltxe2x80x9d constituent is intended to be defined by a fiber or filament having a melt temperature of 280xc2x0 F.-340xc2x0 F. or even greater. Also, in any composite or blended yarn, the high melt constituent should have a melt temperature of at least 40-600xc2x0 F. above that of the low melt constituent. The composite or compounded yarn may be formed in various ways. In one way a continuous filament low melt yarn can be combined with one or more ends of a continuous filament high melt effect yarn with the filament ends being combined during a texturing operation, such as air jet texturing, false twist texturing, twisting, prior twisting, conventional covering and the like. In a second approach, low melt and high melt staple fibers may be homogeneously mixed or blended, then processed according to standard staple yarn processing techniques.
The resulting yarn becomes self-coating and self-bonding in that the low melt constituent or component melts during a subsequent heat operation after fabric formation. Melted polymer then flows through the adjacent fibers or filaments and onto the adjacent effect yarns to bind the individual fabric components. This makes for a stronger fabric. Further, the individual fabric yarns are fixed in place and thereby the fabric structure is stabilized. The melting of the low melt constituent minimizes raveling, and seam slippage, imparts greater load elongation recovery, and greater abrasion resistance, and all without the application of a conventional latex backing. Since the latex backing can be eliminated, the resulting fabric is more esthetically acceptable with the color pattern of the yarns being visible on both sides of the fabric. In a continuous lay down operation for pattern cutting, the fabric is folded exposing alternate sides in the finished product, and therefore the latex backing will not permit this technique.
These and other aspects of the present invention will become apparent to those skilled in the art after reading of the following description of the preferred embodiments when considered in conjunction with the drawings. It should be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate two embodiments of the invention and, together with the description, serve to explain the principles of the invention.